# MCQs on Mirror Formula

**MCQs on Mirror Formula**

**Q1: A convex mirror of focal length f forms an image which is 1/n times the object. The distance of the object from the mirror is **

- (n-1)f
- (n-1/n) f
- (n+1/n) f
- (n+1) f

**Answer: (a) (n-1)f**

**Q2: Consider a concave mirror of focal length 50 cm. Where should the object be placed so that its image is twice the size of the object and inverted**

- 60 cm
- 70 cm
- 75 cm
- 55 cm

**Answer: (c) 75 cm**

**Q3: An object 2 cm high is placed at a distance of 16 cm from a concave mirror, which produces 3 cm high inverted image. What is the focal length of the mirror?**

- -10 cm
- -9.6 cm
- 9.6 cm
- 8 cm

**Answer: (b) -9.6 cm**

**Q4: An erect image 3 times the size of the object is obtained with a concave mirror of radius of curvature 36 cm. What is the position of the object?**

- -12 cm
- 5 cm
- 10 cm
- -21 cm

**Answer: (a) -12 cm**

**Q5: An object is placed at infinity in front of the convex mirror of radius of curvature 40 cm. How far is the image behind the mirror?**

- 20 cm
- 25 cm
- 30 cm
- 35 cm

**Answer: (a) 20 cm**

**Q6: The image formed by a convex mirror of focal length 30cm is a quarter of the object. What is the distance of the object from the mirror?**

- -90 cm
- 60 cm
- -75 cm
- -60 cm

**Answer: (a) -90 cm**

**Q7: Convex mirror is used to form an image of the object. Which of the following statements is wrong?**

- The image is erect
- The image is diminished in size
- The image is real
- The image lies between the pole and the focus

**Answer: (c) The image is real**

**Q8: A lens having a focal distance of 30 cm is placed in front of an object, which is located at 1m from it. Where is an image of the object located?**

- 40 cm
- 42.85 cm
- 52 cm
- 60 cm

**Answer: (b) 42.85 cm**

**Q9: The focal length of a concave mirror is f and the distance from the object to the principle focus is x. The ratio of the size of the image to the size of the object is**

- (f + x)/f
- f/x
- f
^{2}/x^{2}

**Answer: (b) f/x**

**Q10: In a concave mirror experiment, an object is placed at a distance x _{1}**

_{ }

**from the focus and the image is formed at a distance x**

_{2 }from the focus. The focal length of the mirror would be- x
_{1}x_{2} - (x
_{1}+x_{2})/2 - √x
_{1}x_{2} - √x
_{1/}x_{2}

**Answer: (c) **√x_{1}x_{2}